MORPHOMETRIC ANALYSIS OF LANDSLIDE-GENERATING CATCHMENTS IN THE CARSON RANGE, WESTERN NEVADA

Landslides are a common feature in areas of high-relief. Landslide events can have relatively long-lasting effects on the geomorphology of the catchments in which they occur. However, it is not clear how long morphologic evidence of a landsliding event will be preserved, especially in an area with high-relief and relatively rapid erosion. The purpose of this study is to evaluate catchments with landslides of different ages within the Carson Range to assess 1) how long features related to landsliding are recognizable and 2) to determine if any long-lived features could be used to identify areas where landslides occurred, but landslide deposits are no longer exposed.

The Carson Range is located on the western side of the Basin and Range province, between the Reno-Carson City corridor to the east and Lake Tahoe to the west. The range sits at the intersection of the Basin and Range and Walker Lane. The range is bounded on the east by a large east-dipping normal fault, which bifurcates and dies out toward the northern end of the range near Reno. Additionally, the range is cut by many small normal and strike-slip faults. Bedrock within the Carson Range is cored by Mesozoic granitic and metamorphic rock with Oligocene-Miocene volcanic and fluvio-lacustrine units that increase in abundance to the north and east. The highest portions of the range were also glaciated periodically during the Pleistocene. Recently published maps (e.g., Hinz et al., 2018) have separated landslide deposits into at least four different ages, ranging from late Pliocene to late Holocene.

We have compiled data from published maps to identify 18 main landslides and landslide complexes within the Carson Range, dominantly between the northern end of the range and southern Washoe Valley. Using 10-meter DEMs, we will perform geomorphic analyses on the catchments with identified landslides and compare them with catchments that do not have identified landslide deposits. Using scripts developed in MATLAB, we will calculate morphometric parameters, including roughness, slope, curvature, aspect ratio, and anisotropic coefficient of variation. These analyses will be compared to test for systematic variation with age and/or presence of landslide deposits. From this we hope to determine a set of key characteristics to identify catchments affected by landsliding.